Definition - What does Plastic Hinge mean?
A plastic hinge, in structural engineering, refers to the deformation of a part of a beam wherever plastic bending happens. Hinge means that having no capability to resist moment. Therefore, a plastic hinge behaves like a standard hinge - permitting free rotation. The concept of plastic hinge is important in understanding structural failure.
Corrosionpedia explains Plastic Hinge
The quantity of hinges necessary for failure doesn't vary for a specific structure subject to a given loading condition, though an area of a structure could fail severally by the formation of a smaller range of hinges. On paper, plastic hinges are assumed to form at points where plastic rotations occur. Thus, the length of a plastic hinge is taken into account to be zero.
Plastic hinges widen on small lengths of beams. The real values of this lengths depend upon load distributions and cross sections of beams. Elaborated analyses have shown that it is more than correct to think this beams rigid-plastic, with plastic deformation confined to plastic hinges at points. Whereas this assumption is decent for limit state analysis, finite part formulations are offered to account for the unfold of physical property on plastic hinge lengths.